<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="../js/react.development.js"></script>
    <script src="../js/react-dom.development.js"></script>
    <script src="../js/babel.min.js"></script>
    <script src="../js/prop-types.js"></script>
</head>
<body>
    <div id="root"></div>
    <script type="text/babel">
        class InputForm extends React.Component {
            constructor(props) {
                super(props);
                this.state = {
                    value: '',
                };
            }
            handleChange = (e) => {
                this.setState({
                    value: e.target.value,
                })
            }
            handleSubmit = (e) => {
                alert('submit: ' + this.state.value);
                e.preventDefault();
            }
            render() {
                return (
                    <form onSubmit={this.handleSubmit}>
                        <label>
                            value:
                            <input 
                                type="text"
                                onChange={this.handleChange}
                                value={this.state.value}
                            />    
                        </label>
                        <input type="submit" value="submit"/>
                    </form>
                )
            }
        }

        ReactDOM.render(<InputForm/>, document.getElementById('root'))
    </script>
</body>
</html>